How do you connect a motion sensor up with a motor so that when the sensor goes off, it also powers the motor?

This is a project I'm doing for my kinetic sculpture class.  Ideally I would like to have the piece set up in the hallway and have multiple motion sensors so that when it detects someone walking by it, it powers an attached mallet of some sort that hits against the wall to make a beat.  Let me know if you need a better/ more detailed description!

Any help would be greatly appreciated!!

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AndyGadget6 years ago

These PIR sensors would be ideal.  They give an output pulse of several seconds duration when they detect a person in the field of view.
You would have to have a bit of additional circuitry (check out 555 monostable) to make the pulse more controllable, and a drive circuit to power a solenoid to move the mallet.  (The bigger the mallet the harder this bit would be.  What sort of scale are you thinking of?)

BriannaSchmall (author)  AndyGadget6 years ago
this is starting to help. How exactly would the PIR sensor hook up to a motor? If this is a complicated process, I could alter my project a bit. I've just never worked with motion sensors or anything of that sort but would love to incorporate them into my project for my kinetic sculpture! Thanks for the help that you've already given me!
The PIR gives out a signal when it detects a person moving, but that signal has very little 'oomph' behind it - Nowhere near enough to move the weight of a mallet.  It needs additional circuitry to 'gear up' the power.
It will also trigger several times as the person is walking by. That may be what you want, but it's not too difficult to tailor it to your needs with a bit of extra circuitry to control how many times and for how long.
The task is not particularly difficult, but as I'm pretty sure there is no off-the-shelf solution to do this it would take a bit of designing, which I really do not have time to do - sorry.
If this is a college project, is there an electronics department which could help you with the technicalities, or possibly a joint-effort with a technically minded student?
(The way I would do it is with 2 cascaded 555 monostables for the signal conditioning, then a MOSFET driver stage with spike protection. )

BriannaSchmall (author)  AndyGadget6 years ago
Thanks so much for your help! I think I am starting to get it.
76543216 years ago
use a microcontroller?
BriannaSchmall (author)  76543216 years ago
could you explain a little more? I'm very much a beginner when it comes to this kind of stuff.

Thanks for the feedback thus far!!
Go check out the Arduino microcontroller platform. If your intended sensor isn't too complicated it shouldn't be too hard to rig something up (ie. steal bits and pieces of code from elsewhere). If you want to be gutsy and keep your costs down (Sparkfun is a little bit pricier than they need to be sometimes), go check out the TI launchpad, its only $4.30 and I've heard rumors of something enabling you to use Arduino code on the launchpad makig it easier to use, I guess.